This invention relates generally to high-security hasp locks, and more particularly to shackleless cylindrical padlocks which can be used with or without protective guards.
High-security padlocks have become increasingly important in securing truck bodies, slot machines, automatic teller machines and other areas and equipment against unauthorized entry. A number of high-security padlocks have generally short, cylindrical body shapes, and they are sometimes generically referred to as hockey-puck locks. Locks of this sort are shown in Best U.S. Pat. No. 3,404,549; Randel U.S. Pat. No. 3,769,821; and Best U.S. Pat. No. 3,820,360.
To further enhance the security afforded by these locks, guards have been designed to surround the lock bodies and prevent or inhibit the lock bodies from attack by pry bars, jimmies or other instruments. Guards of this short are shown in Perfetto U.S. Pat. No. 5,172,574; and Albano U.S. Pat. No. 5,669,255. Some of these locks and guard systems are relatively expensive to manufacture and are relatively difficult and time-consuming to assemble.
It is a general object of this invention to provide a cylindrical padlock having a relatively great resistance to attack, yet which has relatively few parts and which can be manufactured and assembled relatively quickly and easily.
It is a more specific object to provide a lock of this sort in which the lock mechanism is located entirely within an attack-resistant lock body when the lock is in its locked configuration.
It is another object to provide a shackleless cylindrical padlock in which the lock mechanism is shaped and configured so that it cannot be easily attacked by a drill, jimmy, pry bar, pick, or other tool.
Other objects and advantages of the invention will become apparent upon reading the following detailed description and upon reference to the drawings. Throughout the drawings, like reference numerals referred to light parts.